The Pacific spiny lumpsuckers are tiny, one-inch bony fish. Their bumpy body is full of spiny tubercles, which provide camouflage. The fish have modified pelvic fins that function as adhesive discs, allowing them to remain attached to rocks, eelgrass, and kelp.

The name of this fish describes its appearance funnily. The “spiny” and “sucker” parts of the name are explained in the paragraph above. The lumpy part refers to how the fish resembles a puffy lump.